Fair Value Measurements - Schedule of Share-Based Payment Award Warrant Liability Valuation Assumptions (Detail) (USD $)	1 Months Ended		12 Months Ended
	Oct. 31, 2012	Jun. 30, 2011	Dec. 31, 2013	Dec. 31, 2012
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock price	$ 2.48	$ 4.45	$ 0.72
Exercise Price	$ 3.00	$ 5.00
Term in years	2 years 6 months 4 days	2 years 6 months	5 years
Volatility	79.70%	69.36%	75.68%
Annual rate of quarterly dividends			0.00%	0.00%
Discount rate- bond equivalent yield			1.52%
Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock price			$ 1.17	$ 1.33
Exercise Price			$ 5.00	$ 5.00
Term in years			1 year 10 months 28 days	2 years 4 months 28 days
Volatility			76.03%	95.91%
Discount rate- bond equivalent yield			0.36%	0.29%
Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Exercise Price			$ 1.60	$ 1.60
Term in years			7 months 2 days	1 year 1 month 2 days
Volatility			42.52%	82.75%
Discount rate- bond equivalent yield			0.08%	0.17%